Multimode optical fiber

摘要

A multimode optical fiber waveguide with graded refractive index for lessening modal dispersion depends upon simultaneous grading of both P2O5 and B2O3 within an otherwise generally unmodified silica glass. P2O5 is at a maximum in the axial core region, while B2O3 is generally the only modifier in the peripheral core region. The defined profile, which depends critically upon P2O5 content in the axial composition and somewhat less critically upon the B2O3 peripheral composition content, is near optimum from the standpoint of mode dispersion and remains so for the entire useful range of carrier wavelength (generally defined as from 0.5 to 1.1 mu m). Numerical aperture for fibers of the invention are typically at a level of 0.3.